This invention relates generally to sampling devices, and particularly to sampling devices that remove a core of material from bulk material.
2. Description of the Prior Art
Sampling devices for sampling grain and other materials are known. U.S. Pat. No. 2,896,444, No. 2,688,877, No. 902,049, No. 323,057, No. 230,121, and No. 215,230 disclose grain sampling devices.
In particular, U.S. Pat. No. 2,896,444, No. 2,688,877, No. 902,049, No. 323,057, and No. 230,121 disclose devices that comprise two concentric tube portions, an outer tube portion and an inner tube portion that is rotatable relative to the outer tube portion. Both tube portions have formed in them apertures which, when they are aligned, allow ingress of material into the device and which, when they are not aligned, retain that material in the device for extraction from the bulk material.
Other sampling devices are disclosed in U.S. Pat No. 4,383,583, No. 4,172,385, No. 3,383,131, and No. 1,027,246. U.S. Pat. No. 4,383,583 discloses a soil sampling tool which comprises a hollow tube having a pointed closure at its lower end for soil penetration and a handle at its upper end for manipulation of the tool. A lateral opening is provided adjacent to the lower end to allow soil to enter the tube and fall into a ladle mounted therein. The tool is removed from the soil before the soil sample is removed therefrom using the ladle.
U.S. Pat. No. 4,172,385 discloses a sampling device for use in septic tanks. That device comprises a transparent tube having an external parallel rod which carries a closure plate. The tube is inserted into the tank and the plate is swung into a position against the lower open end of the tube to retain the sample. The plate is retained in position by a spring.
U.S. Pat. No. 3,383,131 discloses a core sampler in the form of a hollow tube having a removable liner and a cutter at its lower end. The sample is retained in the liner by means of a flexible tube portion which closes above the cutter to retain the sample as the device is lifted from its sampling position.
U.S. Pat. No. 1,027,246 discloses a device that is used to obtain samples from peat bogs. The device comprises a hollow tube, within which is mounted a plunger. The plunger is lifted to a first position within the tube to receive a plug of the material being sampled. If the plug is relatively dry, the plug is retained in the tube by frictional resistance. .If the plug is wet, the plunger is moved to a second position so that a vacuum is created in the tube to retain the plug.
In each case discussed above, the sampling device is removed from the bulk material as a whole, that is, none of the prior-art devices allows the sample to be removed from the device prior to removing the device itself from the bulk material. Also, in many cases the sample breaks up during its removal from the device, or during insertion of the device into the bulk material.
Furthermore, none of the devices discussed above can be used to remove a representative core of material from bulk material which is in a firm set state but which can be cut readily by a blade.